KR20100042187A - Thermal management system for fuel cell vehicle - Google Patents

Abstract

PURPOSE: A heat and water management system is provided to secure a space of a thermal management system line, to reduce the number of parts, and to improve layout by replacing a conventional COD(cathode oxygen depletion)/heater. CONSTITUTION: A heat and water management system for fuel cell vehicles in which a water pump(22) and a radiator(24) are installed in a coolant line(20) of a stack has one integral structure of a cooling water line of power electronic parts and a cooling water line of stack by installing the cooling water line of stack to cool power and electronic parts(31) mounted on vehicles.

Description

Heat management system for fuel cell vehicles {Thermal management system for fuel cell vehicle}

The present invention relates to a heat and water management system of a fuel cell vehicle, and more particularly, to a heat and water management system that removes the reaction heat of the stack to the outside of the system in the fuel cell vehicle and controls the operating temperature of the fuel cell stack. .

A fuel cell is a kind of power generation device that converts chemical energy of fuel into electric energy by electrochemical reaction in the fuel cell stack without converting it into heat by combustion. It can also be applied to the power supply of electrical / electronic products, especially portable devices.

As an example of a fuel cell, a polymer electrolyte membrane fuel cell (PEMFC), which is most frequently researched as a power supply for driving a vehicle, is formed on both sides of a membrane around an electrolyte membrane through which hydrogen ions move. Membrane Electrode Assembly (MEA) with a catalytic electrode layer on which electrochemical reactions occur, GDL (Gas Diffusion Layer), which distributes the reactants evenly and delivers the generated electrical energy. And a gasket and fastening mechanism for maintaining the airtightness and proper fastening pressure of the reactor bodies and cooling water, and a bipolar plate for moving the reactor bodies and cooling water.

In the fuel cell, hydrogen as the fuel and oxygen (air) as the oxidant are respectively supplied to the anode and the cathode of the membrane electrode assembly through the flow path of the separator, and the hydrogen is the anode ('fuel electrode' or 'water'). And the oxygen (air) are supplied to the cathode ('air' or 'oxygen', also known as 'reduction electrode').

Supplied to the anode hydrogen is a hydrogen ion (proton, H ⁺⁾ and electrons by the electrode catalyst constructed on both sides of the electrolyte membrane (electron, e ^-) are decomposed into, passed through only the hydrogen ion in the optional electrolyte membrane cation exchange membrane The electrons are transferred to the cathode through the gas diffusion layer and the separation plate which is a conductor.

In the cathode, the hydrogen ions supplied through the electrolyte membrane and the electrons transferred through the separator meet with oxygen in the air supplied to the cathode by the air supply device to generate a reaction. At this time, due to the movement of hydrogen ions, a flow of electrons occurs through an external conductor, and the flow of electrons generates current.

On the other hand, a fuel cell system mounted on a vehicle includes a fuel cell stack that generates large electric energy, a fuel supply device that supplies fuel (hydrogen) to the fuel cell stack, and oxygen in the air, which is an oxidant required for an electrochemical reaction to the fuel cell stack. It is composed of an air supply device for supplying the fuel cell, a heat and water management system (TMS) that removes the reaction heat of the fuel cell stack to the outside of the system and controls the operating temperature of the fuel cell stack.

With such a configuration, the fuel cell system generates electricity by an electrochemical reaction by hydrogen, which is a fuel, and oxygen in the air, and discharges heat and water as reaction byproducts.

In the fuel cell system, since the heat is generated as a reaction byproduct, an apparatus for cooling the stack is essential to prevent the temperature rise of the stack. In addition, the most urgent and difficult problem in the fuel cell system is the strategy of securing cold startability, so the role of the heat and water management system may be important.

As is well known, the cooling water of the TMS line serves as a refrigerant that cools the stack, and is rapidly heated by a heater to be supplied to the stack during cold start, and thus serves to rapidly thaw the stack.

A conventional solution for securing cold startability in fuel cell vehicles has been rapid thawing of pure water using a heater inside a rapid thaw accumulator (RTA). However, when pure water is used, not only does the pure water freeze below the freezing point, but the cooling water loop becomes complicated and additional drain valves are required.

As a solution to this problem, there is a method of using the antifreeze for the stack as the coolant and rapidly cooling the coolant to smoothly generate power of the stack at a temperature below the freezing point. To do this, a heater must be attached to the stack coolant line.

In addition, in fuel cell vehicles, the COD (Cathod Oxygen Depletion) is connected to both terminals of the stack in order to prevent the stack durability from being deteriorated due to corrosion of the catalyst-carrying carbon when the fuel cell is started up or shut down. Power generation by the reaction of is consumed as thermal energy.

1 is a schematic view showing a heat and water management system (TMS) according to the prior art, showing the configuration of a TMS line centered on a fuel cell stack. As shown, a water pump 22 for cooling water circulation, a radiator 24 for heat exchange between outside air and cooling water, a thermostat 23, a COD having a function of load consumption, and a heater 21 for heating the cooling water. It is configured to include, wherein the COD and the heater may be provided in the same cartridge form integrally.

These COD / heater cartridges are expensive and, in particular, in the case of COD, are composed of a plurality of heater rods built in, so that the volume of the COD / heater cartridge is quite large, thus occupying a substantial portion of the total TMS volume. This large volume of COD is very disadvantageous in terms of layout.

In essence, both heater and COD are resistance heaters, which can be integrated into a single heater, with the only difference in usage and usage. Such COD integrated heaters have used all the heat generated by attaching to the stack cooling water circuit to raise the temperature of the stack cooling water. In addition, the COD integrated heater is used to prevent the rapid rise of the coolant to the stack's self-heating temperature during cryogenic cold start, load consumption of the stack during self-heating cold start, and prevention of carbon corrosion of the electrode and anode flooding during fuel cell start-up and shutdown. Was attached separately to the TMS line.

If the COD integrated heater replaces the functions of the COD integrated heater in other drive systems or other load-consumption devices, including the electric power components of fuel cell vehicles, the TMS line can be used to secure space, reduce the number of parts, reduce costs, and improve layout. There will be.

Accordingly, the present invention has been made in consideration of the above-mentioned point, the cooling loop is to replace the function of the existing COD / heater in other load consuming devices such as drive systems or heating and heating parts including electric power components mounted on the vehicle The purpose of the present invention is to provide a heat and water management system for a fuel cell vehicle, which enables space, reduced component count, cost reduction, and improved layout of the entire system.

In order to achieve the above object, the present invention, in the heat and water management system of the fuel cell vehicle is configured by installing a water pump and a radiator in the cooling water line of the stack,

The cooling water line of the stack passes through the power electronic component for cooling the power electronic component mounted in a vehicle, and the cooling water line of the power electronic component and the cooling water line of the stack have a single integrated structure. The coolant circulating between the component and the stack cools the power electronics and warms the stack with the heat provided therefrom.

The present invention also provides a heat and water management system for a fuel cell vehicle comprising a water pump and a radiator installed in a cooling water line of a stack.

A coolant line for cooling the power electronics mounted in the vehicle is provided separately from the coolant line of the stack, and an intermediate heat exchanger is installed between both coolant lines, so that the coolant in the stack passes through the power electronic component in the intermediate heat exchanger. The stack is warmed up by receiving heat from one coolant.

In this case, when the power consumption of the stack is required, the power electronic component is used as a load consuming device that consumes the current of the stack while driving power supplied through a cable connected from the stack.

Accordingly, according to the heat and water management system of the present invention, by replacing the function of the existing COD / heater in other load consuming devices such as drive systems or heating and heating parts including electric power components, to secure space in the TMS line and reduce the number of parts This can result in cost reduction and layout improvement.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

In the present invention, a power electronic component (PE) component mounted in a fuel cell vehicle has a conventional COD (main power consumption of a fuel cell) and a heater (heating of the coolant of the fuel cell and improving the cold startability of the stack). Improving the cooling loop so that the power electronic component consumes the power of the fuel cell so that the heat generated from the power electronic component can be used to heat the cooling water of the fuel cell. We would like to present a water management system.

In fuel cell vehicles, power electronic components such as motors (vehicle driving motors, radiator fan motors, etc.), DCDC converters (LDC (Low Voltage DCDC Converter), etc.), drive systems and heating and heating parts including electric power components such as inverters, etc. Is equipped with a water pipe to cope with self-heating, and the cooling system is configured to supply cooling water through the water pipe so that the cooling water absorbs heat from the corresponding parts.

The present invention is to improve the TMS line so that the role of COD / heater can be replaced by power electronic components, which are heat generating components, the function of the existing COD / heater in other load consumption devices such as drive systems or heating and heating components including electric power components By substituting for the TMS line, it is possible to secure space, reduce the number of parts, reduce costs, and improve layout.

The COD / heater of the TMS line can be eliminated if the power electronic component acts as a load device that consumes the current as the present invention and warms up the stack with the heat generated at that time. However, considering the cold start of the stack, the cooling water circuit of the TMS line should be configured in an optimal arrangement.

2 is a block diagram of a heat and water management system for a fuel cell vehicle according to an exemplary embodiment of the present invention, and FIG. 3 is a block diagram of a heat and water management system according to another embodiment of the present invention.

Referring to FIG. 2, a cooling water line of a power electronic component (PE part) and a cooling water line of a stack are integrated to see a heat and water management system composed of one cooling loop. The water pump 22 for cooling water circulation, the radiator 24 for heat exchange between the cooling water and the outside air, the thermostat 23 and the like are provided in the cooling water line 20 of the stack as in the prior art, and the cooling water is in the water pump 22 Circulating between the stack 10 and the radiator 24 to absorb heat from the stack 10 and release it from the radiator 24.

At this time, the coolant line of the power electronic component is integrated with the coolant line of the stack to form one coolant line 20, and the coolant circulating between the stack 10 and the radiator 24 is generated in the power electronic component 31. It is heated by the heat to be supplied to the stack. In addition, the heat generated by the power electronic components 31 can be released by the radiator 24 after absorbing the cooling water.

As described above, one cooling loop is configured for the power electronic component 31 and the stack 10, wherein the power electronic component 31 receives power generated in the stack through the cable 11 connected from the stack 10. In this case, the power electronic component 31 may consume electric current while driving and receiving power from the stack 10 through the cable 11 when necessary.

Of course, the driving of the power electronic components is controlled by each controller that controls it. For example, in the case of a motor, the driving is performed under the control of the MCU with the fuel cell system controller as the upper controller. In the case of LDC, its own controller (LDC controller) controls its operation.

In the configuration of the single cooling loop as described above, if the power electronic component 31 properly consumes the power of the stack 10 and heats the coolant supplied to the stack with the heat generated at that time, the stack is warmed up, the existing COD and the heater. Without this, the stack's power consumption and cold startability can be improved.

In the configuration of FIG. 2, in order to meet the coolant ion conductivity conditions of the stack, an electrical conductivity sensor or the like may be attached to the coolant line to manage electrical conductivity separately.

Next, referring to FIG. 3, a coolant line 40 of a power electronic component (PE component) and a coolant line 20 of a stack are separately provided, and an intermediate heat exchanger 50 for heat exchange between both coolants is added. Thermal and water management systems can be seen. That is, the cooling water line 40 of the power electronic component and the cooling water line 20 of the stack are configured to have two cooling loops, and an intermediate heat exchanger 50 is installed between the two cooling loops.

Cooling water line 20 of the stack is provided with a water pump 22 for cooling water circulation, a radiator 24 for exchanging outside air and cooling water, a thermostat 23, and the like. 22 is used to absorb heat from the stack 10 while circulating between the stack 10 and the radiator 24 and release it from the radiator 24.

In addition, the cooling water line 40 of the power electronic component is provided with a water pump 41 for circulation of the cooling water, the power electronic component 31 receives the power generated in the stack through a cable 11 connected from the stack 10 It is to be supplied. Accordingly, when necessary, the power electronic component 31 may consume power while driving the power supply of the stack 10 through the cable 11.

The intermediate heat exchanger 50 is for transferring heat between the coolant line 40 of the power electronic component and the coolant line 20 of the stack, and the coolant circulating through the coolant line 40 of the power electronic component is used in the power electronic component ( 31) absorbs the heat generated by the heat transfer to the cooling water of the stack in the intermediate heat exchanger (50), the cooling water of the stack heated in the intermediate heat exchanger (50) flows to the stack 10 to warm up the stack .

As a result, the coolant flowing through the coolant line 40 of the power electronic component basically cools the power electronic component 31, but the coolant cools the power electronic component and is heated at the same time to cool the stack in the intermediate heat exchanger 50. Since heat is transferred to the coolant in the heated stack, the warm water of the stack 10 is warmed up, and thus the power electronic component 31 may replace the function of the existing heater.

In addition, after the stack 10 is warmed, the heat absorbed by the power electronic component 31 may be discharged along the path of the coolant, the intermediate heat exchanger 50, the coolant of the stack, and the radiator 24.

In the above configuration, since the power electronic component 31 properly consumes the power of the stack 10 and heats the coolant supplied to the stack with heat generated at that time, the stack warms up, thus consuming power of the stack without a conventional COD and a heater. And improved cold startability.

In this way, in the present invention, by improving the cooling line so that the power electronic components (PE components) replace the function of the existing COD / heater, it is possible to obtain the effect of securing the space of the TMS line, reducing the number of parts, reducing the cost, and improving the layout. In particular, since the COD, which occupies the largest portion of the total volume of the TMS module box, can be deleted, it has a great effect in terms of volume reduction and space saving of the entire system.

If the COD is applied to the cooling water line as it is in the TMS using heat of the power electronic component as in the present invention, the number of heater rods and the capacity of the COD can be reduced, even when the heater is applied as it is.

1 is a schematic diagram illustrating a heat and water management system (TMS) according to the prior art;

2 is a block diagram of a heat and water management system for a fuel cell vehicle according to an embodiment of the present invention;

3 is a block diagram of a heat and water management system according to another embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

10 fuel cell stack 20 stack coolant line

21: COD / heater 22: water pump

24: Radiator 30: Cooling water line of power electronic components

31: power electronic parts (PE parts) 32: water pump

40: intermediate heat exchanger

Claims (4)

In the heat and water management system of a fuel cell vehicle configured by installing a water pump 22 and a radiator 24 in a cooling water line 20 of a stack, The cooling water line 20 of the stack is provided to pass through the power electronic component 31 for cooling the power electronic component 31 mounted in a vehicle so that the cooling water line of the power electronic component and the cooling water line of the stack are integrated. And a coolant circulating between the power electronic component 31 and the stack 10 cools the power electronic component 31 and warms up the stack 10 with heat provided therefrom. And a heat and water management system for a fuel cell vehicle. The method according to claim 1, The power electronic component 31 is used as a load consuming device that consumes the current of the stack while driving and receiving power through a cable 11 connected from the stack 10 when the load of the stack is required. Heat and water management system for fuel cell vehicles. In the heat and water management system of a fuel cell vehicle, which is formed by installing a water pump 22 and a radiator 24 in a coolant line 20 of a stack, A coolant line 40 for cooling the power electronic component 31 mounted in a vehicle is provided separately from the coolant line 20 of the stack, and the intermediate heat exchanger 50 is disposed between both coolant lines 20 and 40. Is installed, the coolant of the stack receives heat from the coolant passing through the power electronic components 31 in the intermediate heat exchanger 50 to warm up the stack 10, characterized in that the heat and water for a vehicle Management system. The method according to claim 3, The power electronic component 31 is used as a load consuming device that consumes the current of the stack while driving and receiving power through a cable 11 connected from the stack 10 when the load of the stack is required. Heat and water management system for fuel cell vehicles.

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